Drilling apparatus

ABSTRACT

An apparatus for drilling a borehole with a drill tool driven in rotation by a motor suspended from the end of a drill column constituted by a flexible drill pipe, this apparatus including a basket for storing the flexible pipe, this basket having an annular shape with a vertical axis, motor means driving said annular basket in rotation about its vertical axis, means for supplying the flexible pipe with drilling fluid during the rotation of said basket, at least one means for driving the flexible pipe between said storage basket and said driving means, wherein said fluid supplying means are constituted by a hydraulic rotary coupling having an annular shape, centered on said vertical axis of the annular storage basket, said hydraulic coupling having an inner diameter at least equal to the maximum outer diameter of said flexible pipe, said vertical axis of the annular basket being substantially in line with the axis of the drilled borehole, said driving means being placed substantially along the borehole axis for displacing said flexible pipe along said axis, said guiding means being adapted to place siad flexible pipe substantially along the borehole axis.

[ Dec. 11, 1973 DRILLING APPARATUS [75] Inventors: Jean Thiery, Le Peco;Pierre Grolet,

Orgerus, both of France [73] Assignee: lnstitut Francais du Petrole, des

Carburants et Lubrifiants, Rueil-Malmaison, France [22] Filed: July 21,1972 [21] Appl. No.: 273,708

[301 ueisae z ieet snRaquela? July 22, 1971 France 7 1 26 960 [52] US.Cl 175/103, 175/162, 175/203,

[51] Int. Cl E2111 7/00, E2lb 19/00 [58] Field of Search 166/77, 85;175/57,

[56] References Cited 1 UNITED STATES PATENTS 2,016,067 10/1935Bannister 175/103 2,548,616 4/1951 Priestman et a1... 175/103 3,306,3572/1967 Cullen et a1. 175/103 X 3,313,346 4/1967 Cross 166/77 X 3,559,9052/1971 Polynchuk.. 166/77 X 3,702,223 11/1972 Bednar 175/103 X 3,667,5546/1972 Smitherman 166/77 X FOREIGN PATENTS OR APPLICATIONS 2,443 1/1905Great Britain 175/103 996,063 6/1965 Great Britain 175/103 1,191,0385/1970 Great Britain 175/162 Primary Examiner-David H. BrownAttorney-Craig & Antonelli [57] ABSTRACT An apparatus for drilling aborehole with a drill tool driven in rotation by a motor suspended fromthe end of a drill column constituted by a flexible drill pipe, thisapparatus including a basket for storing the flexible pipe, this baskethaving an annular shape with a vertical axis, motor means driving saidannular basket in rotation about its vertical axis, means for supplyingthe flexible pipe with drilling fluid during the rotation of saidbasket, at least one means for driving the flexible pipe between saidstorage basket and said driving 1 means, wherein said fluid supplyingmeans are constituted by a hydraulic rotary coupling having an annularshape, centered on said vertical axis of the annular storage basket,said hydraulic coupling having an inner diameter at least equal to themaximum outer diameter of said flexible pipe, said vertical axis of theannular basket being substantially in line with the axis of the drilledborehole, said driving means being placed substantially along theborehole axis for displacing said flexible pipe along said axis, saidguiding means being adapted to place siad flexible pipe substantiallyalong the borehole axis.

3 Claims, 1 Drawing Figure PATENTED DEC 1 1 191a DRILLING APPARATUS Thepresent invention relates to a new drilling apparatus particularlyadapted to the drillingoperations using a bottom motor driving a drilltool, this motor being suspended from the end of a flexible drill pipe.

The drilling methods known in particular in the art under the name offlexo-drilling and using as drill stem a flexible pipe, have now animportant develop ment. This is, in particular, the consequence of thetechnological improvements permitting the fabrication of highperformance pipes. However the drilling device employed up to now, whichmake use of such flexible drill pipes, are directly derived from theconventional drilling equipments employing rigid drill strings.

They include in particular, above the borehole, a derrick used forhandling the rigid tubular components which must be connected to thelower part of the flexible pipe such as bottom motor, drill-collars andtubing elements for the borehole.

These prior devices suffer therefore from the drawback of a greatvertical bulkiness.

Moreover the flexible pipe is coiled on a winding device or stored in arotary basket at some distance from the drilled borehole. These priordevices have consequently also a great horizontal bulkiness.

The main object of the present invention is accordingly to permit theelimination of the aforementioned drawbacks and in particular to allowto substantially reduce the vertical and horizontal bulkiness of thedrilling device.

These and other objects are achieved with an apparatus for drilling aborehole by means of a drill tool driven in rotation through a motorsuspended from the end of a drill column constituted by a flexible drillpipe, this apparatus including a basket for storing the flexible pipe,this basket having an annular shape with a vertical axis, motor meansdriving said annular basket in rotation about its vertical axis, meansfor supplying the flexible pipe with drilling fluid during the rotationof said basket, at least one means for driving the flexible pipe andmeans for guiding the flexible pipe between said storage basket and saiddriving means, wherein said fluid supplying means are constituted by arotary coupling having an annular shape, centered on said vertical axisof the annular storage basket, said hydraulic coupling having an innerdiameter at least equal to the maximum outer diameter of said flexiblepipe, the vertical axis of the annular basket being substantially inline with the axis of the drilled borehole, said driving means beingplaced substantially along the borehole axis for displacing saidflexible pipe along said axis, said guiding means being adapted to placesaid flexible pipe substantially along the borehole axis.

The invention will be better understood and other advantages thereofwill be made apparent from the following description of a non-limitativeembodiment of this invention illustrated by the accompanying drawing.

This drawing is a front view of a device according to the invention,diagrammatically illustrated in crosssection.

This device according to the invention comprises a rotary basket 1 forstoring the flexible drill pipe 2,

a diagrammatically illustrated rotary coupling 3 for the drilling fluidsupply of the pipe 2 during the rotation of the basket 1,

a return. device 5, whereby the flexible pipe 2 is guided between thestoring basket 1 and the handling device 4.

The storage basket 1 may be of any known type, in particular of the typedescribed in the Patent application Ser. No. 264,470 filed in the US.Patent Office on June 20, 1972.

The storage basketillustrated in the drawing comprises a firstcylindrical wall 6 having a substantially vertical axis, a secondcylindrical wall 7 coaxial with the first wall, these two walls definingtherebetween an annular space 8 having a width at least equal to thediameter of the flexible drill pipe. The space 8 is limited at its lowerpart by a base plate 9 of annular shape, which supports the verticalwalls 6 and 7. At its upper part the space 8 is open for permitting thepassage of the flexible pipe 2. Under the platform 9 is secured acircular rail 10 coaxial with the annular basket. This rail rests on aplurality of wheels 11 of which only two have been illustrated for sakeof clarity of the drawing.

One or more of these wheels, which are carried by stationary bearings12, are driven in rotation by motors 13 which may be of the hydraulic orelectric type.

The storage basket 1 is provided with a hydraulic rotary coupling 3having an annular shape and coaxial with the basket. 1.

This coupling includes an annular stationary element or ring 30,substantially U-shaped, at the bottom of which is provided a circulargroove 16, connected to a pipe 14, one end of which is connected to thering 3a, for example by threading, the other end of this pipe beingconnected to a source of drilling fluid (not shown), and a ringorannular element 3b having a shape complementary to that of the ring 3aand being rotatable with respect to the latter.

The ring 3b is fast in rotation with the storage basket 1. A duct 15connects one end of the drill pipe 2 to the ring 3b to permit thedrilling fluid supply of the pipe 2 coiled in the storage basket 1,through the pipe 14, the groove 16 and a conduit 17 provided in the ring3b.

Sealing means (not shown) prevent any fluid leakage between the surfacesin contact of rings 3a and 3b.

As apparent from the drawing, the use of an annular rotary couplingmakes it possible to keep free the central part of the basket 1.

Of course the rotary coupling 3 may have an internal diameter greaterthan the external diameter of the basket l or alternatively may belocated under the base plate of the latter, the illustrated embodimentbeing by no way limitative.

The basket for storing the flexible pipe is so located that its verticalaxis be in line with the axis of the drilled borehole 18.

This arrangement permits a reduction in the bulkiness of the drillingapparatus, which constitutes a very important advantage, particularlywhen the drilling operations are performed from a floating drillingplatform.

A device 4 for handling the drill pipe is located substantially alongthe axis of the borehole 18. This device may be of any known type. Inparticular, as diagrammatically shown in the drawing, it will bepossible to make use of an endless chain conveyor which displaces thedrill pipe along the vertical axis of the storage basket.

A fixed return device 3 provides for the guiding of the flexible drillpipe between the storage basket 1 and the device 4 for handling thispipe. This device 5 comprises a curvilinear guiding path having in-eachpoint a radius of curvature at least equal to the minimum radius ofwinding of the pipe 2.

The control of the handling device 4 and of the engines 13 driving inrotation the storage basket will preferably be synchronized through anyknown means diagrammatically shown at 19, so as to facilitate thewinding or unwinding of the flexible pipe coiled in the storage basket1.

Modifications may be made different without departing from the scope ofthe present invention.

In particular, in the case where the drill pipe is provided whithincorporated electrical lines for remote measuring, remote controllingor power transmitting, the continuity of the electric circuits may beensured through the rotary coupling 3, by equipping the same for examplewith sliding electric contacts etc.

What we claim is:

1. An apparatus for drilling a borehole with a drill tool driven inrotation by a motor suspended from the end of drill column constitutedby a flexible drill pipe, this apparatus including a basket for storingthe flexible pipe, this basket having an annular shape with a verticalaxis, motor means driving said annular basket in rotation about itsvertical axis, means for supplying the flexible pipe with drilling fluidduring the rotation of said basket, at least one means for driving theflexible pipe and means for guiding the flexible pipe between saidstorage basket and said driving means, wherein said fluid supplyingmeans are constituted by a hydraulic rotary coupling having an annularshape, centered onsaid vertical axis of the annular storage basket, saidhydraulic coupling having an inner diameter at least equal to themaximum outer diameter of said flexible pipe, said vertical axis of theannular basket being substantially in line with the axis of the drilledborehole, said driving means being placed substantially along theborehole axis for displacing said flexible pipe along said axis, saidguiding means being adapted to place said flexible pipe substantiallyalong the borehole axis.

2. A device according to claim 1, comprising means for synchronizing thecontrol of said handling device and of said motor means driving inrotation said annular basket.

3. A device according to claim 1, wherein said rotary coupling isconstituted by at least two coaxial annular elements, one of saidelements being stationary and the other fast in rotation with saidstorage basket, at least one of said annular elements being providedwith at least one circular groove, said groove being, on the one hand,fed with hydraulic fluid through a first duct connecting said stationaryannular element to a source of hydraulic fluid and communicating, on theother hand, with said flexible pipe through a second duct connectingsaid annular element fast in rotation with the basket to one end of saidflexible pipe carried by said annular basket.

1. An apparatus for drilling a borehole with a drill tool driven inrotation by a motor suspended from the end of drill column constitutedby a flexible drill pipe, this apparatus including a basket for storingthe flexible pipe, this basket having an annular shape with a verticalaxis, motor means driving said annular basket in rotation about itsvertical axis, means for supplying the flexible pipe with drilling fluidduring the rotation of said basket, at least one means for driving theflexible pipe and means for guiding the flexible pipe between saidstorage basket and said driving means, wherein said fluid supplyingmeans are constituted by a hydraulic rotary coupling having an annularshape, centered on said vertical axis of the annular storage basket,said hydraulic coupling having an inner diameter at least equal to themaximum outer diameter of said flexible pipe, said vertical axis of theannular basket being substantially in line with the axis of the drilledborehole, said driving means being placed substantially along theborehole axis for displacing said flexible pipe along said axis, saidguiding means being adapted to place said flexible pipe substantiallyalong the borehole axis.
 2. A device according to claim 1, comprisingmeans for synchronizing the control of said handling device and of saidmotor means driving in rotation said annular basket.
 3. A deviceaccording to claim 1, wherein said rotary coupling is constituted by atleast two coaxial annular elements, one of said elements beingstationary and the other fast in rotation with said storage basket, atleast one of said annular elements being provided with at least onecircular groove, said groove being, on the one hand, fed with hydraulicfluid through a first duct connecting said stationary annular element toa source of hydraulic fluid and communicating, on the other hand, withsaid flexible pipe through a second duct connecting said annular elementfast in rotation with the basket to one end of said flexible pipecarried by said annular basket.